NECASA II: A Practical Algorithm Integrating Skincare in the Management of Adult Female Acne in the Nordic European Countries
November 2025 | Volume 24 | Issue 11 | 9196 | Copyright © November 2025
Published online October 31, 2025
Peter Bjerring MD Dr Scia, Oxana Anckar MDb, Anneke Andriessen PhDc, Carl Kyrklund MD PhDd, Alison Layton MB FRCPe, Anne Birgitte Nordal MDf, Cristina Oprica MD PhDg
aDepartment of Dermatology, Aalborg University Hospital, Aalborg, Denmark
bDiagnostisk Centrum Hud in Stockholm, Sweden
cRadboud UMC, Nijmegen and Andriessen Consultants, Malden, The Netherlands
dSkin Hospital/Suomen Ihosairaala, Finland
eClinical Lead Skin Research Centre, University of York, United Kingdom
fHudklinikken, Oslo, Norway
gDiagnostiskt Centrum Hud, Stockholm, Karolinska Institutet, Department of Laboratory Medicine,
Division of Clinical Microbiology; Stockholm, Sweden
Abstract
Background: Adult female acne presents challenges, including increased prevalence, distinct clinical manifestations, heightened skin sensitivity, treatment-related intolerance, and reduced treatment adherence. Integrating skincare into acne management is essential, particularly in Nordic European countries, where environmental factors influence skin physiology. The Nordic European Countries Acne Skincare Algorithm (NECASA) II algorithm serves as an evidence-based practical tool for clinicians in this region to select appropriate skincare based on individual patients' needs to optimize acne care for adult females.
Methods: Dermatologists from six Nordic European countries met to develop the NECASA II algorithm, which builds on the NECASA I framework. The advisors conducted a structured literature review and, combined with their clinical experience, established best practice recommendations for integrating skincare into adult female acne treatment regimens.
Results: The NECASA II algorithm recommends integrating skincare into adult female acne management based on acne severity, subtype, and patient characteristics. The panel concluded that all acne regimens should incorporate a physiologic pH cleanser, an emollient with humectants and lipids, and SPF 50+ sunscreen. Skincare monotherapy is recommended for mild acne, adjunctive skincare for moderate-to-severe acne, and maintenance skincare to prevent relapse following treatment.
Conclusions: Personalized skincare regimens, combined with prescription and nonprescription treatments, can mitigate adverse effects, improve treatment tolerance and adherence, and enhance overall outcomes.
INTRODUCTION
Acne vulgaris (Acne) is a prevalent inflammatory skin condition that can cause lifelong physical consequences, including dyschromia and scars, leading to social and psychological impacts.1-3 While commonly associated with adolescence, adult acne affects approximately 40% of patients in their 20s and persists into the 30s in almost half of adults.1 Acne poses a substantial healthcare burden, ranking as the 8th most prevalent disease globally in 2010 and causing 20 years lived with disability per 100,000 people.4,5 The socioeconomic impact of acne is evidenced by the US's treatment costs and productivity losses exceeding $3 billion annually.1 Acne severely impacts quality of life (QoL) and is associated with low self-esteem, anxiety, depression, suicidal ideation, and negative emotions, including embarrassment, humiliation, and self-consciousness.1,3,6 These effects are amplified in women due to societal pressures related to appearance.3,4,6,7 Acne etiology is multifactorial, involving a complex interplay of genetic, hormonal, and environmental factors.8-10 While the current understanding of acne pathophysiology is incomplete, key acne-initiating factors include altered sebum production and microbiome dysbiosis, leading to inflammation and follicular hyperkeratinization.8,10 Epidermal barrier disruption is a major driver of acne pathogenesis and severity, particularly in adult female acne.7,10,11 The epithelial barrier is directly involved in inflammation, comedogenesis, and particularly in follicular rupture.10,12,13 Consequently, restoring the epidermal barrier and the microbiome by controlling Cutibacterium acnes
